{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T23:30:50Z","timestamp":1777591850729,"version":"3.51.4"},"reference-count":59,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2017,1,7]],"date-time":"2017-01-07T00:00:00Z","timestamp":1483747200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Due to a lack of appropriate image resolution, most ultrasound scanners are unable to sensitively discern the pulley tissues. To extensively investigate the properties of the A1 pulley system and the surrounding tissues for assessing trigger finger, a 30 MHz ultrasound system was implemented to perform in vitro experiments using the hypodermis, A1 pulley, and superficial digital flexor tendon (SDFT) dissected from cadavers. Ultrasound signals were acquired from both the transverse and sagittal planes of each tissue sample. The quantitative ultrasonic parameters, including sound speed, attenuation coefficient, integrated backscatter (IB) and Nakagami parameter (m), were subsequently estimated to characterize the tissue properties. The results demonstrated that the acquired ultrasound images have high resolution and are able to sufficiently differentiate the variations of tissue textures. Moreover, the attenuation slope of the hypodermis is larger than those of the A1 pulley and SDFT. The IB of A1 pulley is about the same as that of the hypodermis, and is very different from SDFT. The m parameter of the A1 pulley is also very different from those of hypodermis and SDFT. This study demonstrated that high-frequency ultrasound images in conjunction with ultrasonic parameters are capable of characterizing the A1 pulley system and surrounding tissues.<\/jats:p>","DOI":"10.3390\/s17010107","type":"journal-article","created":{"date-parts":[[2017,1,9]],"date-time":"2017-01-09T11:03:23Z","timestamp":1483959803000},"page":"107","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Quantitative Assessment of First Annular Pulley and Adjacent Tissues Using High-Frequency Ultrasound"],"prefix":"10.3390","volume":"17","author":[{"given":"Yi-Hsun","family":"Lin","sequence":"first","affiliation":[{"name":"Department of Computer Science and Information Engineering &amp; Institute of Medical Informatics, National Cheng Kung University, No. 1, University Road, Tainan City 70101, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tai-Hua","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, National Cheng Kung University, No. 1, University Road, Tainan City 70101, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6586-0138","authenticated-orcid":false,"given":"Shyh-Hau","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Information Engineering &amp; Institute of Medical Informatics, National Cheng Kung University, No. 1, University Road, Tainan City 70101, Taiwan"},{"name":"Medical Device Innovation Center, National Cheng Kung University, No. 1, University Road, Tainan City 70101, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fong-Chin","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, National Cheng Kung University, No. 1, University Road, Tainan City 70101, Taiwan"},{"name":"Medical Device Innovation Center, National Cheng Kung University, No. 1, University Road, Tainan City 70101, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,1,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1333","DOI":"10.7863\/jum.2005.24.10.1333","article-title":"High-frequency ultrasonographic examination of the finger pulley system","volume":"24","author":"Boutry","year":"2005","journal-title":"J. Ultrasound Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1148\/radiology.217.1.r00oc40201","article-title":"Pulley system in the fingers: Normal anatomy and simulated lesions in cadavers at mr imaging, ct, and us with and without contrast material distention of the tendon sheath","volume":"217","author":"Hauger","year":"2000","journal-title":"Radiology"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"527","DOI":"10.1016\/j.csm.2006.02.001","article-title":"Injuries of the fingers and thumb in the athlete","volume":"25","author":"Peterson","year":"2006","journal-title":"Clin. Sports Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"949","DOI":"10.1016\/S0363-5023(89)80043-7","article-title":"Functional anatomy of the human digital flexor pulley system","volume":"14","author":"Lin","year":"1989","journal-title":"J. Hand Surg. Am."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"473","DOI":"10.1016\/S0363-5023(88)80082-0","article-title":"Anatomy of the finger flexor tendon sheath and pulley system","volume":"13","author":"Doyle","year":"1988","journal-title":"J. Hand Surg. Am."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1016\/j.jassh.2004.11.009","article-title":"Biomechanics of the digit","volume":"5","author":"Gonzalez","year":"2005","journal-title":"J. Hand Surg. Am."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1012","DOI":"10.2106\/00004623-199807000-00010","article-title":"Pathomechanics of closed rupture of the flexor tendon pulleys in rock climbers","volume":"80","author":"Marco","year":"1998","journal-title":"J. Bone Jt. Surg. Am."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"246","DOI":"10.5435\/00124635-200107000-00004","article-title":"Trigger digits: Diagnosis and treatment","volume":"9","author":"Saldana","year":"2001","journal-title":"J. Am. Acad. Orthop. Surg."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1455","DOI":"10.1007\/s00296-009-1165-3","article-title":"Ultrasonographic assessment of clinically diagnosed trigger fingers","volume":"30","author":"Kim","year":"2010","journal-title":"Rheumatol. Int."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"387","DOI":"10.1007\/s002560000226","article-title":"Sonographic evaluation of digital annular pulley tears","volume":"29","author":"Martinoli","year":"2000","journal-title":"Skelet. Radiol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1007\/s002560050488","article-title":"High-frequency ultrasound examination of the wrist and hand","volume":"28","author":"Bianchi","year":"1999","journal-title":"Skelet. Radiol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1407","DOI":"10.7863\/jum.2008.27.10.1407","article-title":"Sonographic appearance of trigger fingers","volume":"27","author":"Guerini","year":"2008","journal-title":"J. Ultrasound Med."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1441","DOI":"10.7863\/jum.2009.28.11.1441","article-title":"Sonographic depiction of trigger fingers in acromegaly","volume":"28","author":"Tagliafico","year":"2009","journal-title":"J. Ultrasound Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"254","DOI":"10.1016\/j.ejrad.2010.05.013","article-title":"The thickness of the a1 pulleys reflects the disability of hand mobility in scleroderma. A pilot study using high-frequency ultrasound","volume":"77","author":"Tagliafico","year":"2011","journal-title":"Eur. J. Radiol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1486","DOI":"10.1016\/j.jhsa.2011.05.038","article-title":"Stiffness of the first annular pulley in normal and trigger fingers","volume":"36","author":"Miyamoto","year":"2011","journal-title":"J. Hand Surg. Am."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2012","DOI":"10.1016\/j.jhsa.2012.06.027","article-title":"Sonographic appearance of the flexor tendon, volar plate, and a1 pulley with respect to the severity of trigger finger","volume":"37","author":"Sato","year":"2012","journal-title":"J. Hand Surg. Am."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1109\/10.594895","article-title":"An approach for measuring ultrasonic backscattering from biological tissues with focused transducers","volume":"44","author":"Wang","year":"1997","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"757","DOI":"10.1088\/0031-9155\/56\/3\/014","article-title":"Quantitative assessments of burn degree by high-frequency ultrasonic backscattering and statistical model","volume":"56","author":"Lin","year":"2011","journal-title":"Phys. Med. Biol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"157","DOI":"10.5405\/jmbe.936","article-title":"Estimation of cell concentration using high-frequency ultrasonic backscattering","volume":"32","author":"Chen","year":"2012","journal-title":"J. Med. Biol. Eng."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"79","DOI":"10.5405\/jmbe.893","article-title":"Review: Study of the blood coagulation by ultrasound","volume":"31","author":"Huang","year":"2011","journal-title":"J. Med. Biol. Eng."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1971","DOI":"10.1016\/j.ultrasmedbio.2007.06.004","article-title":"Determining the acoustic properties of the lens using a high-frequency ultrasonic needle transducer","volume":"33","author":"Huang","year":"2007","journal-title":"Ultrasound Med. Biol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0301-5629(99)00096-4","article-title":"Advances in ultrasound biomicroscopy","volume":"26","author":"Foster","year":"2000","journal-title":"Ultrasound Med. Biol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1121\/1.397238","article-title":"Ultrasonic backscatter from flowing whole blood. I: Dependence on shear rate and hematocrit","volume":"84","author":"Yuan","year":"1988","journal-title":"J. Acoust. Soc. Am."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1567","DOI":"10.1016\/j.ultrasmedbio.2005.07.003","article-title":"Detection of blood coagulation and clot formation using quantitative ultrasonic parameters","volume":"31","author":"Huang","year":"2005","journal-title":"Ultrasound Med. Biol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1191","DOI":"10.1016\/j.ultrasmedbio.2007.02.009","article-title":"High frequency ultrasound assessment of skin fibrosis: Clinical results","volume":"33","author":"Huang","year":"2007","journal-title":"Ultrasound Med. Biol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1177","DOI":"10.1016\/0301-5629(95)00049-6","article-title":"Ultrasonic propagation properties of excised human skin","volume":"21","author":"Moran","year":"1995","journal-title":"Ultrasound Med. Biol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1307","DOI":"10.1121\/1.413054","article-title":"Comparison of the anisotropy of apparent integrated ultrasonic backscatter from fixed human tendon and fixed human myocardium","volume":"97","author":"Hoffmeister","year":"1995","journal-title":"J. Acoust. Soc. Am."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1345","DOI":"10.1016\/j.ultrasmedbio.2004.08.009","article-title":"The effect of transducer characteristics on the estimation of nakagami paramater as a function of scatterer concentration","volume":"30","author":"Tsui","year":"2004","journal-title":"Ultrasound Med. Biol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1109\/T-SU.1978.30978","article-title":"Speckle in ultrasound b-mode scans","volume":"25","author":"Burckhardt","year":"1978","journal-title":"IEEE Trans. Sonics Ultrason."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"910","DOI":"10.1364\/JOSAA.4.000910","article-title":"Statistical properties of radio-frequency and envelope-detected signals with applications to medical ultrasound","volume":"4","author":"Wagner","year":"1987","journal-title":"J. Opt. Soc. Am. A"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2992","DOI":"10.1121\/1.400818","article-title":"Ultrasound speckle analysis based on the k distribution","volume":"89","author":"Weng","year":"1991","journal-title":"J. Acoust. Soc. Am."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1177\/016173469401600404","article-title":"Ultrasound echo envelope analysis using a homodyned k distribution signal model","volume":"16","author":"Dutt","year":"1994","journal-title":"Ultrason. Imaging"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1633","DOI":"10.1088\/0031-9155\/40\/10\/006","article-title":"A model for ultrasonic scattering from tissues based on the k distribution","volume":"40","author":"Shankar","year":"1995","journal-title":"Phys. Med. Biol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"727","DOI":"10.1109\/58.842062","article-title":"A general statistical model for ultrasonic backscattering from tissues","volume":"47","author":"Shankar","year":"2000","journal-title":"IEEE Trans. Ultrason. Ferroelectr. Freq. Control"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1109\/TUFFC.2003.1193628","article-title":"A compound scattering pdf for the ultrasonic echo envelope and its relationship to k and nakagami distributions","volume":"50","author":"Shankar","year":"2003","journal-title":"IEEE Trans. Ultrason. Ferroelectr. Freq. Control"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"371","DOI":"10.1016\/j.ultrasmedbio.2005.11.012","article-title":"Study of ultrasonic echo envelope based on nakagami-inverse gaussian distribution","volume":"32","author":"Karmeshu","year":"2006","journal-title":"Ultrasound Med. Biol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"608","DOI":"10.1016\/j.ultrasmedbio.2006.10.005","article-title":"Imaging local scatterer concentrations by the nakagami statistical model","volume":"33","author":"Tsui","year":"2007","journal-title":"Ultrasound Med. Biol."},{"key":"ref_38","unstructured":"Wang, S.H., Tsai, F.C., and Hung, Y.L. (2001, January 7\u201310). Characterization of bony tissues from ultrasonic backscattering using statistical models. Proceedings of the International Ultrasonics Symposium, Atlanta, GA, USA."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"871","DOI":"10.1109\/TUFFC.2002.1020157","article-title":"Statistics of envelope of high-frequency ultrasonic backscatter from human skin in vivo","volume":"49","author":"Raju","year":"2002","journal-title":"IEEE Trans. Ultrason. Ferroelectr. Freq. Control"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1109\/58.911740","article-title":"Classification of ultrasonic b-mode images of breast masses using nakagami distribution","volume":"48","author":"Shankar","year":"2001","journal-title":"IEEE Trans. Ultrason. Ferroelectr. Freq. Control"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"027002","DOI":"10.1143\/JJAP.48.027002","article-title":"The effect of kinetic properties on statistical variations of ultrasound signals backscattered from flowing blood","volume":"48","author":"Huang","year":"2009","journal-title":"Jpn. J. Appl. Phys."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"353","DOI":"10.1109\/T-SU.1979.31116","article-title":"Estimating the acoustic attenuation coefficient slope for liver from reflected ultrasound signals","volume":"26","author":"Kuc","year":"1979","journal-title":"IEEE Trans. Sonics Ultrason."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"970","DOI":"10.1109\/TUFFC.2012.2282","article-title":"Quantitative assessment on the orientation and distribution of carbon fibers in a conductive polymer composite using high-frequency ultrasound","volume":"59","author":"Lin","year":"2012","journal-title":"IEEE Trans. Ultrason. Ferroelectr. Freq. Control"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"7738","DOI":"10.3390\/s140507738","article-title":"Assessment of the kinetic trajectory of the median nerve in the wrist by high-frequency ultrasound","volume":"14","author":"Lin","year":"2014","journal-title":"Sensors"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1016\/j.memsci.2013.01.020","article-title":"Distribution and deposition of organic fouling on the microfiltration membrane evaluated by high-frequency ultrasound","volume":"433","author":"Lin","year":"2013","journal-title":"J. Membr. Sci."},{"key":"ref_46","unstructured":"Shung, K.K. (2006). Diagnostic Ultrasound: Imaging and Blood Flow Measurements, CRC Press. [1st ed.]."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"2308","DOI":"10.1121\/1.1452743","article-title":"Frequency-dependent attenuation-compensation functions for ultrasonic signals backscattered from random media","volume":"111","author":"Oelze","year":"2002","journal-title":"J. Acoust. Soc. Am."},{"key":"ref_48","doi-asserted-by":"crossref","unstructured":"O\u2019Donnell, M., Bauwens, D., Mimbs, J.W., and Miller, J.G. (1979, January 26\u201328). Broadband integrated backscatter: An approach to spatially localized tissue characterization in vivo. Proceedings of the International Ultrasonics Symposium, New Orleans, LA, USA.","DOI":"10.1109\/ULTSYM.1979.197186"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1016\/0301-5629(88)90181-0","article-title":"Measurement of ultrasonic nonlinear parameter in excised fat tissues","volume":"14","author":"Errabolu","year":"1988","journal-title":"Ultrasound Med. Biol."},{"key":"ref_50","first-page":"201","article-title":"Observations on the elastic tissue of the skin with a note on the reticular layer at the junction of the dermis and epidermis","volume":"81","author":"Dick","year":"1947","journal-title":"J. Anat."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1109\/TBME.1981.324789","article-title":"Clinical imaging with transmissive ultrasonic computerized tomography","volume":"28","author":"Greenleaf","year":"1981","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1109\/T-SU.1985.31602","article-title":"Speed of sound in mammalian tendon threads using various reference media","volume":"32","author":"Edwards","year":"1985","journal-title":"IEEE Trans. Sonics Ultrason."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"3225","DOI":"10.1121\/1.414866","article-title":"Ultrasonic properties of tendon: Velocity, attenuation, and backscattering in equine digital flexor tendons","volume":"99","author":"Miles","year":"1996","journal-title":"J. Acoust. Soc. Am."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"1275","DOI":"10.1016\/S0301-5629(01)00442-2","article-title":"Elastic properties of tendon measured by two different approaches","volume":"27","author":"Kuo","year":"2001","journal-title":"Ultrasound Med. Biol."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"1075","DOI":"10.1016\/j.ultrasmedbio.2015.12.007","article-title":"Identification of the position and thickness of the first annular pulley in sonographic images","volume":"42","author":"Yang","year":"2016","journal-title":"Ultrasound Med. Biol."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"1543","DOI":"10.1016\/S0301-5629(01)00456-2","article-title":"High-frequency ultrasonic attenuation and backscatter coefficients of in vivo normal human dermis and subcutaneous fat","volume":"27","author":"Raju","year":"2001","journal-title":"Ultrasound Med. Biol."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1016\/0301-5629(79)90083-8","article-title":"Ultrasonic attenuation and propagation speed in mammalian tissues as a function of temperature","volume":"5","author":"Bamber","year":"1979","journal-title":"Ultrasound Med. Biol."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"907","DOI":"10.1016\/0301-5629(96)00085-3","article-title":"Factors affecting the ultrasonic properties of equine digital flexor tendons","volume":"22","author":"Miles","year":"1996","journal-title":"Ultrasound Med. Biol."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"1038","DOI":"10.1118\/1.3292633","article-title":"Ultrasound b-scan image simulation, segmentation, and analysis of the equine tendon","volume":"37","author":"Meghoufel","year":"2010","journal-title":"Med. Phys."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/1\/107\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:25:41Z","timestamp":1760207141000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/1\/107"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,1,7]]},"references-count":59,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2017,1]]}},"alternative-id":["s17010107"],"URL":"https:\/\/doi.org\/10.3390\/s17010107","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,1,7]]}}}